Xray result diagnosis are different.

Why does my X-ray results from two different clinics was different? The first clinic diagnosed me with fibrosis vs subsegmental atelectasis but my newest X-ray from a different clinic shows a clear lung. The tests was taken 3 days apart. I had to undergo the first  chest xray as i had a flu but with no cough nor a fever only my body aches and fatigue. I also recently quit smoking for 8 yrs before i had the first xray. I am currently taking antibiotics for my nasal congestion and other meds. i dont have any history of lung disease before as well, and my last year chest xray was clear as well. It is just suddenly pop ups so im currently confused of why i was diagnosed like that easily at first. thanks!